Snow chains have recently become known, in which the rear holding device consists of a spring steel bracket, which is circular, but not closed. In order to mount this spring-steel bracket on a tire the bracket can be grasped by the operator with both hands and easily extended in diameter until it can be passed quickly over the tire to the inner side of the tire. The open ends of the spring-steel bracket are bridged by means of a tension chain, which is attached to one end of the bracket and passed through a ring at the other. The free end of the tension chain, after being passed through the guide ring, is passed over the running surface of the tire in such a way that it remains on the outer side of the tire, even while the chain is being mounted. Should the spring-steel bracket slip out of position on the inner side of the tire, a vigorous pull is applied to the free end of the tension strand on the outside and, by so doing, the rear holding device; i.e. the spring-steel bracket, is again seated tightly. In order to complete the mounting of this previously known anti-skid chain, it is necessary, after slipping the spring-steel bracket over the tire and giving the tension strand an initial tightening, to move the vehicle backwards or forwards by a small distance, since only after so doing does it become possible to tighten the tension strand to achieve the desired seating of the rear holding device. This is because the tension strand bridging the two ends of the rear holding device is passed through the guide ring before the holding device is slipped over the vehicle tire. Consequently, it is unnecessary to thread the tension strands into the ring after slipping the spring-steel bracket over the inner side of the tire. However, after the chain is put on, the wheel must be turned to finally tighten the rear holding device.
An anti-skid device is also known in which the rear holding device consists of three, individual, rigid sections instead of a spring-steel bracket (German Offenlengungsschrift No. 2,020,452, FIG. 15). When mounting this three part anti-skid device, the two rigid side sections, which are movably connected to the two ends of the middle section, are swivelled to move them apart so the holding device can be slipped over the tire. Subsequently, however, the operator must reach around the tire to its inner side in order to bring the ends of the side sections together by hand and attach them to each other by some suitable means. After this, the outer holding device must be tightened in a similar manner. This previously known construction enables the anti-skid device to be completely mounted, even when the vehicle tires are stuck, so that the final seating of the snow chains can be achieved without maneuvering the vehicle. The handling of such previously known snow chains while mounting is, however, very cumbersome and requires a certain amount of dexterity on the part of the operator. Furthermore, since the chains generally must be put on under unfavorable weather conditions, the operator also usually becomes quite dirty.